Fill your sink completely full with hot/warm water. Add 1/2 cup of bleach to the water. Now add all the toys to the water. Let them soak for about 2 hours. Once they have soaked you can let the water out of the sink. No fill the water back up but add dish soap to it. You can now scrub and wash those toys. Be sure to squeeze all the water and soap out of each toy a few times. That way you get all the bleach out of them and soap. You would hate to have your kids squeeze that bleach into their mouths. Dry the toys and then they are squeaky clean.
This method uses vinegar rather then bleach. Which can be a chemical free way to go with cleaning the toys. Fill the sink up with water and pour about 1 cup of white vinegar to the water. Add all the toys into the sink. Let soak for a few hours. Sometimes I will do this right before I go to bed, and let them soak over night. That way they get extra clean. In the morning rinse them off and squeeze all the water out of them a couple of times. Then let dry.
When you kids get done taking a bath toss all their toys in the dish washer. The water in the dish washer gets hot enough that it kills all the bacteria in them. But be sure when they are done to squeeze all the water out of them. Sometimes their might still be mold in them. If their is you can put them in some soapy water and squeeze it through a few times. It should come out easy.
Once you have cleaned the toys with whatever method you prefer you can close the holes up on the bottom of each of the squeezy ones. You can do this by taking a hot glue gun and gluing the holes up.
There you have it. Now that you have cleaned the kids bath toys you are going to want to clean their regular toys. You can use the same methods to clean them as well.